Their biological father.
Your husband cannot get joint custody of your children from a prior marriage. Custody arrangements are made between parents of children. Your present husband can legally adopt your children with their father's consent. He would then have all the legal rights and obligations of a biological father. The children would become his legal heirs-at-law.
You divorce and get custody over your kids or just get full custody!
You will need a lawyer to try and get you full custody of your children and your lawyer will have to prove your husband is abusive to his children. If you presently have duel custody of your children and you take the children to the UK you could be charged with kidnapping.
Generally, if married he has custody rights equal to the mother unless she has brought a petition for sole custody in his absence. If he is not married his custody rights must be established by a court order.
The rights your ex-husband will have once you divorce will all depend on what the judge rules. He could have joint custody or split custody.
If you are not divorced then both parents have equal rights regarding custody, decision making and control of the children. If a couple chooses to live apart one party must obtain a court order to get sole custody of the children. That party would need to convince the court the other parent is unfit and awarding sole custody to the moving party is in the best interest of the children. A husband would not be favored for sole custody simply on the basis of being a man. There must be extenuating and serious circumstances for the court to award custody to one parent. You should consult with an attorney in your jurisdiction who can review your situation and inform you of your rights.
It depends if he has custody of the children but afterwards if necessary he may be supervised by a responsible person.
The father will find it easier to get the custody of the children , as the wife has left both the husband and as well as the children and is least interested in them.
both
No, unless a custody order is being violated, it is not kidnapping for the Father to move out of state with his own children.
Boyfriend or husband (unless he is the biological father) has no legal right to the child at all. The mother can try to go for full custody though.
Custody rulings have nothing to do with who files for the divorce first.