Death and rats

Question
One of my rats died last night I found her this morning.She is survived by her sister (Littlefoot) I was wondering how my remaining rat will take her death and if getting her another companion would be a good idea or even if thats possible. I think they really loved each other and I don't want to see her pine away like dogs do.

Answer
Hi Raya

Oh now, thats so sad. I am really sorry for your loss.  Was she sick? How old was she?

As for rats being depressed, you bet they can get very depressed. Sometimes they stress so bad they end up getting sick and dying too and in turn sometimes the vet will think the rat caught what the deceased rat had, but the truth is, the rat was so depressed the stress lowered their immune system and they became ill too.  I have had male rats mourn their cagemate to the point they stop eating and act like they dont care about anything else.  Its very sad.  rats are very social animals so I would not hesitate to bring in a pair of females for her, and why do I say a pair ?   This will break the cycle of always ending up with a lone rat. I usually say to buy at least 3 rats so they always have each other if one passes away unless you lose them back to back etc...  
Start out with a pair of girls younger than Littlefoot so she can feel like the alpha female with on questions asked.

You will need to quarantine the new girls for 3 weeks before introductions. Once it is over, you can put the girls in a cage by Littlefoots cage so they can smell each other.  Slowly over about a weeks time you will introduce them and usually they click right away.