so my mom and I live together and about a year ago she began to talk to her mother after years of them not really having a relationship.

now my "grandma" lives with us and it hasn't been a bad experience as much as just awkward. I have respect for my elders as well as those in authority but I'm just downright lost.

My Grandma is different. I think she has been through a lot and I'm not sure if she's all "there" (if you catch my drift)

She grew up rough I'm assuming and so makes snyde remarks and comments about my sister who grew up with no struggles Materialistically and is really sarcastic and snyde.

she lives here in our home. has her own room (the biggest besides my moms) and pretty much just lays around all day. she's retired. I understand she gets bored so she will just start "re decorating" the house and what not. for the most part its all petty. but she also has a tendency to talk behind our backs especially to us girls about my mom and says things about her past or how she behaved as a child.

I'm just wondering if this Is a sign of Alzheimer's if so how should I go about this ?

. she can also be weird at times. talks to herself or I catch her saying malicious things to our animals when we aren't around (I'll hear her at night in her room or as I'm coming in from work at night) what should I do ?

I care about her but I'm concerned. and also a little scared.