Divorce Advice for Men | Fathers Rights Divorce | Child Custody

My ex-husband and I have been apart for 3 years and have recently finalized our divorce. We have 3 children together and share custody. Recently, it has been verified that my 3rd child is not his. We are currently resolving that and there are no issues as far that is concerned (he is willing to give me sole custody with visitation for him). However, his mother and stepfather are angered by this and trying to step in on our business. They tried to butt their way into our mediation for the child in question by filing a motion to amend custody (they want custody of all three children). The mediation center has told them that they are not welcome to the mediation. Because of this mess, they have now filed for custody of all three children(one being non-biological) because they want control. My ex and I are on great terms and have a custody agreement in place already. He has them for the school year and I have them every other weekend and during the summer (per our agreement in mediation). I absolutely agree that even though my ex is not my daughter's father, that he should still have rights to her since he has raised her for 6 years. My question is.....do the grandparents have any rights to take them from us? In my heart I know have the constitutional right to raise our children?

Trying to be brief; My wife filed the papers on 2-21-08. Within the papers she said we had been separated since 11-19-07. Also within the papers she had listed all of our assets (inheritance unknown and not mentioned) On 2-15-08 my grandfather died. On 3-15-08 I learned my inheritance was $25,000, along with my son (age 7) who also inherited $25,000 In Vermont you have to wait 6 months until a final order is given. The temporary order has us 70/30 physical custody and 50/50 legal custody. My question is whether my 25k is considered marital property? I also want to ensure the 25k for my son stays intact until he is at least 18. With joint legal custody I feel confident that this will happen (I was also named trustee in the will) but I need some reassurance and any advice here as well.

My divorce was final the beginning of 2007. My ex quit his job where he was making 150k+ per year one month before the divorce was final. My ex told the judge and everyone else that he was working for a particular company. It turns out, he NEVER worked for the company he claimed and is instead doing a business in sales under the table. He is doing the exact same type of sales as with his $150k job. He does not know that I know this. He continues to talk about his "fake job" and how that's going. I am 100% positive on these facts. I'm thinking he will try to reduce child support in a year. It has been 6 months and he is still keeping up the act of having a factious job. Should I confront him or allow him to continue the lie until he tries to change the child support?