If people like the time frame, this comic is between 1792 and 1859. The 15th state was Kentucky, and the 33rd state was Oregon. The description saying "removing stripes" is referring back to when the US was first adding states beyond the original 13, they added a stripe 14 for Vermont in 1791 and 15 for Kentucky in 1792, it was decided in 1818 that the flag would officially only have 13 stripes
As for America calling France mom, I wonder if this foster mom situation is like his country got independence, but since he's a kid he had to live with an adult, but he can't live with England, so France took him in
@AmericanButterfly
There could be two reasons France is America's Mom: 1) France was America's main ally during the War for Independence, or 2) the Louisiana Purchase, which roughly doubled the size of the original country. Or maybe both of those.
13