Thank you for the information firstly, you are going to have to employ a lawyer who specialises in family law but please let me help put your mind at ease. Firstly, just because they are/were married she may not have any rights to the house, it will depend on the circumstance, now while she may not have any rights to the house itself, she is likely to have some rights to stay there for a time as it was potentially the marital home and the home of his child, who I'm sure he wouldn't want to make homeless, but that is potentially a bit of good news moving forward. Secondly. If you cannot agree on access with the children then you will have to seek the lawyer to make an application to the court for a child contact order the order will set out when he gets access to the children. The court will not look favourable upon her if she is being deliberately difficult for no reason other than dislike of your partner. Secondly, when he has time with his children, unless the court states otherwise, he can see and take them wherever he likes (not out the country though as he needs her or the courts permission for that, one of the other will do so keep that in mind if you are looking to book a holiday abroad may be an idea to seek an order from the court before booking). Even if she objects to the children going the grandparents house, the only reason the court would prevent it would be if there was any type of danger to the children which from what you are saying that sounds highly unlikely. But the short answer is go instruct a lawyer, these things can take time so I wouldn't hesitate too much, a family lawyer should be able to help with both the children situation and also the house situation (which is likely to be the more complicated of both issues).
I hope this information has helped. You can find a local solicitor who deals with this on the law society webpage which is;
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