First grandchild

so I am not sure if I have already posted this or not --I have been so slack lately. But my oldest son and his 17 year old girlfriend are having a baby !! And instead of being more excited I was depressed. not because my kid was having a kid but because these 16 and 17year old girls get pregnant so damn easily ..It just seems so dang unfair . I have adjusted to the fact and am happy and ready to be a grandma to this baby, because I know how precious children are. And as sad as it is gonna sound when I say this - I think if it would have been a girl I would have been  in a horrible state of jealousy and depression.It is a boy and they have chosen the name Caleb Daniel ( after my husband) -- I have come to terms with it and am getting excited and hope that I will get to spend tons of time with him, And I know that the minute I look into his litte eyes I am gonna fall in live for sure. As y'all knoe my oldest three are not my biological children but I have been with them since they were 7month, 2 and 3 1/2  their birth mother  has seen them less than ten times in 16 years -- so as far as the kids and I are concerned I AM MOMMY !!!   Scott and I had our issues because he has oppositional defiant disorder and is schizo-effect disorder.. and I am the one who bore the brunt of all his anger and mood swings-- So I really hope that a grandchild makes our bond closer and he doesn't try to push me out of the baby's life out of spite.. He has seemed to grow up and matured a little and we do get along a lot better now that he isn't living at home,