My daughter who is 41 , lives with me, and is an alcoholic, but calls her children every night. I am always within hearing distance. The step Mom listens in and if she doesn't like the conversation or the question my daughter asks she hangs up the phone on them and won't answer the phone if my daughter calls back. There are never questions asked that are inapropriate. Just things like "did you go to the reunion," did you eat some good food" and the last one was, "why did your sister get to make the choice of whether it would be the carneval or the reunion". Click, the phone was hung up. I have heard the step Mom and Dad of only 2 years are having trouble getting along , and I feel the step Mom is taking it out on the kids. I know how this Man treated my daughter and she doesn't have an easy way to go, and I tired to warn her not to marry him But... So what would or should I as there Grandmother say to either of them? Or shouldn't I say anything?

It also sounds like they could be having trouble because he sees she is controlling and maybe even gets some of that control shoved at him.
You really can't say anything. The father either needs to grow a backbone and stick up for him and the kids or your daughter needs to go to court and have it put in whatever order they have in place that she quit influencing her relationship with her kids negatively.

Does your daughter have visitation/the RIGHT to be calling in a legal court order?

If so, the step mother could be held in contempt of court for not allowing the calls to take place. If she has a court order, I would say this would be the first place to start.

Have to spread the rep yes she is in contempt and it is not her place to interfere with the mothers relationship.