Q. If a woman marries for a second time, can the husband be a Mahram for the children from the first marriage, ie. would the daughters from the first marriage be allowed to go for umrah with the step dad?
A. As long as there is no fear of Fitna (corruption), the daughters of the first marriage can go for Umrah with their stepfather since he is their Mahram.
And Allah knows best.
Mufti Majid Khan