In January My Older Brother Passed Away.....they Said It Was

In January my older brother passed away.....they said it was ALS......this really surprised me because 6 months before there was no mention of Als…….He became Ill after a knee replacement about 1 year before his death, he went down hill in a hurry, it was scary....He was 86....I am 74 and I was diagnosed with PD 32 months ago and sometimes I wonder if this is correct...….