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LGBT+ History Month: Avoiding the pitfalls of platonic multi-parenting within LGBTQIA+ families

Posted on 22 February 2024

Modern families come in a variety of different shapes and sizes, and there are an increasing number of pathways to parenthood for LGBTQIA+ couples. One such emerging pathway is the multi-parent family, often referred to as "platonic parenting", whereby same-sex couples choose to co-parent with single adults (often close friends) or other same-sex couples. As a result, the child can have more than two parental figures.

Where adults are happy to embrace the concept of a platonic multi-parent family, this article explores the pitfalls to consider and how to prevent disputes from arising at the outset.

Legal multi-parenthood and parental rights

In the UK, a child can only have two legal parents. Therefore, any other adult wishing to act as a parent for a child and be involved in important decisions in relation to their upbringing will need to apply to the Court for parental responsibility, as explored further below. In multi-parent families, the crucial first step is determining which parents will need to apply for parental responsibility. This is critical because if an adult has neither legal parenthood nor parental responsibility, they are left with no legal ties to or duties towards the child.

Trans people can become biological parents in different ways, including trans men preserving their fertility and carrying their own biological children, and trans women preserving sperm and creating children through surrogacy. For cis same-sex couples, there are three common scenarios to consider:

  1. A male same-sex couple co-parenting with a single female
    In this scenario, it is assumed that the single female has conceived the child using sperm donated by one of the men in a same-sex couple. The legal position is that the birth mother and male donor i.e. biological father will become the legal parents of the child. Therefore, the donor's partner is a non-legal parent and will need to apply to the Court for parental responsibility in respect of the child.
  2. A female same-sex couple co-parenting with a single male
    In this scenario, it is assumed that the single male has donated sperm to one of the women in a same-sex couple via artificial insemination. There are multiple outcomes here depending on the circumstances of conception.

    If the female same-sex couple are married or in a civil partnership, section 42 of the Human Fertilisation and Embryology Act 2008 ("HFEA 2008") provides for the wife or civil partner of the birth mother to become a second legal parent of the child, unless it is shown that she had not consented to the mother's treatment. Where the female same sex-couple are unmarried under section 43 of the HFEA 2008, if conception has taken place in a registered fertility clinic and the "agreed female parenthood conditions" under section 44 of the HFEA 2008 are met, then again, the birth mother's partner will be treated as a second legal parent. As a result, the sperm donor i.e. the biological father would not be a legal parent and would need to apply for parental responsibility.

    If the female same-sex couple are otherwise unmarried, the default legal position is that the birth mother and sperm donor are the legal parents of the child. Therefore, the birth mother's partner is a non-legal parent and will need to apply for parental responsibility.
  3. Two same-sex couples co-parent together
    In this scenario, the legal positions explained above will apply, such that the birth mother and sperm donor will be the legal parents, unless the birth mother is married or in a civil partnership, in which case the second female parent will become the legal parent. The two non-legal parents will need to apply for parental responsibility.

    It is important to note that if a child is conceived in a registered fertility clinic in these circumstances, all four parents should be able to decide who the second legal parent will be.

Parental responsibility

Parental responsibility is defined as "all the rights, duties, powers, responsibilities and authority which by law a parent of a child has in relation to the child and his property" (Children Act 1989, section 3(1)). In reality, it gives the parent responsibility for making all important decisions in the child's life such as education, religion and medical care, together with day-to-day decisions such as nutrition and recreation. As explained in the section above, parents in certain scenarios will need to apply to the Court for parental responsibility or enter into a parental responsibility agreement so that they have a say in these decisions.

Non-legal parents can also agree the child's living arrangements between them, or, in the absence of agreement, apply to the Court for a Child Arrangements Order which governs a child's living arrangements and ensures that time would be divided on an appropriate basis between all parents. If the court make a Child Arrangements Order in favour of a non-legal parent, naming them as a person with whom the child shall live, that non-legal parent will have parental responsibility for the child for the duration of the order.

Co-parenting disputes and how to avoid them

Multi-parenting arrangements can lead to disputes if each parent's expectations and responsibilities are not clearly defined before the child is born. Disputes can in turn lead to protracted litigation, causing unnecessary delay, costs and acrimony when making decisions in relation to the child's upbringing.

For example, disagreements may arise in relation to:

  • Living arrangements e.g. how the child's time should be split between two households;
  • Education and childcare arrangements;
  • Medical decisions;
  • Financial responsibilities and contributions;
  • Foreign travel or permanent relocation;
  • Morals, values, religion and disciplining;
  • The child's surname; and
  • How and when the child will be told about their conception.

The most effective way to prevent such issues from arising would be to enter into a co-parenting agreement before the child is born. This can address each of the issues above, and more, in order to create a framework for joint decision-making. As each family has unique needs, the development of a bespoke agreement encourages the parents and those who will share parental responsibility to sit down and discuss the decisions that are relevant to them. The agreement can then be reviewed and adapted as the child grows up to reflect the parents' evolving wishes and responsibilities.

It is important to be aware that co-parenting agreements are not legally binding documents. Therefore, if disputes do result in court proceedings, the existence of the agreement will not determine the outcome of proceedings. The Court ultimately exercises its discretion based on an assessment of what is in the child's best interests, with reference to a variety of physical, emotional and social factors at the time.

Nonetheless, the existence of a co-parenting agreement may carry weight by demonstrating the parties' intentions from the outset to the Court. Importantly, it will reduce the potential for disagreements about what was agreed before the child was born.

In practical terms, there are no legal requirements to formalise a co-parenting agreement, but insofar as it will set out the arrangements for many important aspects of the child's upbringing, parties are encouraged to enter into such an agreement on an informed basis, having taken early legal advice where possible. 


Platonic multi-parenting is another significant and positive development to add to the growing list of modern family structures. However, parents entering into these arrangements need to be aware of its limitations in regard to legal parenthood and need to anticipate the potential for conflict. Before the child is born, parents would benefit from taking time to understand the workings of parental responsibility and the importance of a co-parenting agreement in order to ensure a successful and collaborative parenting journey.

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