A man with an young child on is shoulders. Is it possible to determine paternity where the potential fathers are identical twin brothers?

Is it possible to determine paternity where the potential fathers are identical twin brothers?

Jasmin Talai, Senior associate in the Russell-Cooke Solicitors, family and children team.
Jasmin Talai
3 min Read

Senior associate Jasmin Talai examines a recent, rare and complex case of determining paternity when the potential fathers are identical twins.

In the recent case of Re Child A and Child B (Paternity: Identical Twins) (2024) an issue arose that most people have probably never considered: is it possible to determine paternity where the potential fathers are identical twin brothers?

Case background

The mother first met identical twin brothers at a church in 2017. In the early days of knowing them the mother says that she found it difficult to tell which brother was which.

The mother went on to have a sexual relationship with one of the brothers for a few months in 2017. It was during that time that she fell pregnant. She later, when four months pregnant, started a sexual relationship with the other brother.

The child was born in 2018.

The mother and second brother registered the child’s birth together and named him as the child’s father. However, there were allegations of domestic abuse in this case and the mother states that she only did so due to pressure from the second brother, despite knowing that he could not possibly be the child’s father. 

Paternity dispute

A dispute later arose over paternity and in 2023, the first brother, who supported the mother’s timeline of events, applied to the court for a declaration of parentage.

The second brother refused to accept this timeline and claimed that he, and not his brother, was the child’s biological father.

DNA testing

Standard DNA testing produced a positive result for each of the brothers. This confirmed that one of the men was the child’s father but it was not possible to establish which one.

The parties’ solicitors made enquiries to try to establish whether there was another form of testing that could be carried out.

  • King’s College London said that it might be possible to carry out testing of the entire genome to establish whether there were sufficient differentiating factors to establish paternity. However, they stated that a conclusive result could not be guaranteed and ultimately declined to accept an instruction
  • DNA Legal responded that they could undertake a full genome sequencing at a cost of £90,000 (£75,000 + VAT). However, the test would only be able to offer a 95% confidence level (in contrast to 99.8% for standard testing) and would take three months to complete

The cost was far beyond the means of the parties and Cafcass (who in some private law cases can be directed to arrange and fund DNA testing). 

Following a fact-finding hearing, HHJ Reardon found that both men had sex with the mother within the likely window for conception and therefore it was possible that either could be the child’s father. However, she was simply unable to determine on the facts and evidence available to her which one was indeed the child’s father.

What next?

HHJ Reardon suggested a possible way forward:

  1. that the judgment could be sent to the Ministry of Justice to consider whether discretionary funding for the test offered by DNA Legal should be made available; and
  2. that the child may need to be joined as a party so that they can be separately represented through an experienced children’s guardian ‘who can advise the court in these difficult, and possibly unique, circumstances

Ultimately, it has not yet been possible to establish the identity of the child’s father. The real question however, is will it ever be possible?

Even if public funding is made available from the Ministry of Justice, or indeed if this were a case where the parties had sufficient resources to pay for the DNA Legal testing, it seems that the result would not necessarily be conclusive.

An extremely interesting case to read about and an impossible situation for the Judge. However, a sad and unfortunate situation for the family and particularly the child in the middle of all this who will potentially go on to live their life without ever having that clarity or certainty.

Specialist lawyers in the children team at Russell-Cooke are frequently instructed to represent children in highly sensitive and complex cases. 

This case shows how challenging and complex children cases can be. At the heart of every case is the child and no matter who we represent in proceedings we hope to help improve the outcomes for the children concerned. Sometimes however, as this case shows, the answer is not always obvious.
Amy Chapman
Amy Chapman • Legal director

Jasmin Talai is in the family and children team, advising on a wide range of family law matters arising from the breakdown of relationships or where there are disputes relating to children. Amy Chapman is a legal director in the same team advising parents, children and other family members in both private and public law proceedings.

Get in touch

If you would like to speak with a member of the team you can contact our children law solicitors by email, by telephone on +44 (0)20 3826 7528 or complete our enquiry form.

Briefings Family and children Re Child A and Child B (Paternity: Identical Twins) [2024] paternity dispute DNA testing identical twins declaration of parentage biological father full genome sequencing