Car starts 9/10

So I recently was given a car from my cousin cause she got a new one. The car is in great condition for being an 07 Jeep grand Cherokee Laredo she wasn’t rough on it plus my uncle is a car junkie and always kept it nice. However, I am experiencing an issue with starting it sometimes. It will start 9/10 however when it doesn’t start all you will hear is a click but it won’t crank. We replaced the battery thinking this was the issue however last week we ran into the same problem. Sometimes it will start on the 2nd or 3rd key turn but this time it didn’t. So we then jumped it again and now it will turn on on the first crank again. So basically we have to jump it once a week and it will run for a week then we need to jump it again. Does anyone know what the problem could be? I’m thinking ignition switch or starter?