We're both right...its a long evolving holiday apparently, the recognition of Lincoln started around the same time that I was starting grade one in New Jersey:  

The Uniform Monday Holiday Act also included a provision to combine the celebration of Washington’s birthday with that of Abraham Lincoln, which fell on February 12. Lincoln’s Birthday had long been a state holiday in places like Illinois, and many supported joining the two days as a way of giving equal recognition to two of America’s most famous statesmen.

https://www.history.com/topics/holidays/presidents-day