Solved: Simple question

When I check my ping, it is usually fine until my friend streams on youtube but in my friends house, when I youtube, he does not lag in-game. Are there any ways that I can do in order to allow my friend to stream without me lagging? For example, My sister and mom will stream videos on youtube while I play my online game but I won't lag, is it possible?

I have 2 extra routers just incase it is needed for this case