Call my son Jack (after my very dear GFather - lost my own father so GFather was like my dad) when my SIL and Brother named their sone Jackson.
Children will have different surnames and only see each other at family events, attend different schools etc. SIL and Bro did know I always intended to name a son Jack if I went on to have a son however aware that no one owns a name and they was well in their rights to also use the name they love also after said relative
I am now doubting if I can use the name but only because of people’s opinions. The name is very sentimental and I would ultimately be upset if I had to settle for another name