We are new grandparents in our 50's. Our 18 year old sons' 15 year old girlfriend gave birth to their son just before our son turned 19. Our son and his girlfriend are now separated and I don't know if they will ever get back together. Our 7 month old grandsons' mom is making it hard for us to see our grandson now. Do we have any legal rights as his paternal grandparents to be allowed visitation rights? We are good, honest, well-balanced and hard working, people and have a very happy and secure home. We are well known in the community and have never been in any trouble with the law. We just want to be able to enjoy our grandson. We live in Minnesota.

First son has visit rights, so when he goes and picks up the child for his weekend you get to see the child. This is easiest.

After that to get any rights you have to file in court.

Minn does allow for grandparent's visitation, but it does not appear you meet the guidelines:

Grandparent's Rights in Minnesota

I also think your son has to worry about her parents preferring statutory rape charges. It's a close call according the MN law. Since she was between 13 and 16, he would have to have been 4 yrs older to be safe.

So before he tries to get joint custody and visitation, you need to see if he is safe from criminal prosecution. If he is, then as soon as the baby is born, he needs to file for joint custody and visitation. The mother will probably file child support.