For the RCC: Once there is one godparent or a godmother & godfather sufficient for the sacramental celebration, one can presumably name as many extra godparents as one wants. But be prepared that only one or two will be officially recorded in the baptismal registry and on the baptismal certificate.
Whether all these extra godparents will be able to participate in the baptismal ceremony on a par with the ‘official godparent(s)’ is up to the minister. It’s my recommendation to meet with the minister face to face in advance and get permission. Of course, if parents, godparents, and family and friends all gather round the font at the same time, the point of who’s godparents and who’s not is moot.
Of course, doesn’t the status of being a godparent kind of get diluted if there are thirteen other godparents? At some point, naming extra godparents becomes counter-productive.
I hope that they indicated this in a will, for it’s a common misperception that the ‘godparents’ will be the ones to raise the children in the death of the parents – not according to the courts if you die intestate. Without a will, the courts will assign the children to whom the courts think they should go, regardless of who has ‘godparent’ status. The courts tend to look to immediate relatives first.
What name do you give your child?