The Chief Executive of Barnardo’s, Anne Marie Carrie, is urging peers in the House of Lords to support the Marriage (Same Sex Couple) Bill and says “equal marriage will have a positive effect for children growing up in a gay household.”

When the marriage bill is debated in the House of Lords for the first time on Monday I will be interested to hear what peers have to say about the impact on children and families. I suspect we may hear some peers worry about the negative effects that equalising marriage will have on children. As someone who has worked with vulnerable young people for thirty years, I am confident that equal marriage will have a positive effect for children growing up in a gay household.

Through our work at Barnardo’s in adoption and fostering, we know that different kinds of families are equally able at providing safe and loving homes for children in need. It’s the commitment, skills and resourcefulness of parents which makes the difference for young people, not the gender of their partner. That’s why Barnardo’s believes same-sex couples should have equal rights to legal recognition, and it’s time to demonstrate that the law values families headed by same-sex couples just as much as those headed by heterosexual partners.

Whilst this view may be seen as controversial by some, it is shared with many others. For example, when I recently met the TV presenter Clare Balding and her partner Alice Arnold, they were quick to praise Barnardo’s stance and emphasised the importance of encouraging good self-esteem in children from different family backgrounds. Removing the legal distinction between same-sex and heterosexual families is an important contribution to helping children of gay parents stand proud of who they are and where they come from.

Recognising and celebrating the families of same-sex couples is also an important encouragement to LGBT people considering fostering and adoption. The number of children looking for new homes is growing every year, and we need more same-sex couples to join the variety of individuals and couples who provide supportive, thriving families for vulnerable children. Unfortunately some of the arguments used against equal marriage, however they were intended, give the impression that LGBT parents are less preferable to heterosexual ones.

During the debate about equal marriage in the House of Commons last week, a number of MPs expressed the view that the purpose of marriage is to create an environment for the birth and raising of children, something which would apparently be lost if same-sex couples were allowed to marry. Of course we should be careful not to denigrate the efforts of those parents already doing a great job of raising children outside the current bounds of marriage. But allowing same-sex couples to marry if they choose would bring more loving parents and their children into the institution, not fewer.

Opening up marriage to same-sex couples will remove one of the last remaining legal inequalities between different kinds of couples. It will give young LGBT people and the children of same-sex partners a boost when they face unkind words from people whose views on sexuality will not be changed overnight by changing the law. When they stand up to speak on the marriage bill I hope peers will be thinking of these families.

Anne Marie Carrie is the chief executive of Barnardo’s, the UK’s largest children’s charity.