son is as you say, feeling threatened and insecure. If all three of you can get on, the children will sense this and may behave in a different way. Many girls share a bed with their sister and find it great fun if they get on. The key is getting them to like one another and enjoy each other's company. You should discuss your concerns and work out whether this is rivalry or something more serious. Ultimately, you all need to work together to encourage all four children to be kind to one another and enjoy the new family unit. Best Regards Harjit Sarang, Partner and Head of Family Law BEST Solicitors LLP Q. I separated from my sons father 9 months ago we were not married, my son is 8 and was born 20/02/03 he has introduced my son to his new girlfriend he has been seeing his new girlfriend foor aprrox 6 weeks with a fall out in between and he has been working away for 3 weeks so i believe it to be far too ealy days to involve my son.. I have stated that my ex can have continued accessas he has always done on the basis he doesnt involve my son yet for approx 6mths, he did not collect his son and told him it was because he was at his girlfriends house this is the 1st time he has not seen his son and also not paid maintenance, am i right to request he