Have you ever heard of Angel Numbers? So when my sister was still alive [I Angels Do Exist]

we made a pact that whom ever died first would somehow communicate with the one still alive in some way. To let the other know they were ok. So after she died I kept seeing 11 11. Whether it be on my clock, on a receipt, a random number in the paper, or my change I'd get back from buying something. I'd see 11 11 everywhere. So I started thinking ...me and my sister are 11 months apart, and it struck me as kinda weird . So like 2 years later I was still seeing these numbers and someone told me that 11 11 was an Angel number. And it was a loved one trying to communicate with me. I was a little shocked but then I remembered our pact. I then knew that my sister was telling me that she was ok. I still see the numbers 13 years later.