Like the title says, does your LO know how to dial 911?

I talk to my oldest about this frequently since I'm solo a lot and I want them to be able to get help if there is an emergency and I'm unable to be the one to call. Thankfully he knows how to do it! Actually writing this made me realize that I've taught him how to use our landline, but maybe I should teach him how to use a cell in case that isn't an option?