Does the father have the right to take his two children from the custody of their maternal grandmother due to the presence of harm (the grandmother smoking), and is the father more entitled to custody after the grandmother or the mother, knowing that the age of custody in Egypt is until 15 years?

If the female custodian is immoral or incapable, or if there is a fear of harm to the children from her, then her custody is forfeited and transfers to the one who is more deserving of it.

If the guardian of the child travels a distance of six burud for permanent residence, he has the right to take the child with him, and the female custodian is given the choice between moving with them or forfeiting her custody.

If you reside outside Egypt, you have the right to take the children to you. The same applies if you fear harm to them, such as the presence of a smoker, because cohabiting with a smoker exposes one to diseases, and this is sufficient reason to transfer custody. How much more so if this is combined with the fear of this reprehensible habit spreading to the child.