renal lymphoma in 2 year old female

Question
My daughter and I purchased baby bunnies, 2 females, same litter.  We let them play together often. Recently we noticed, Snips, my daughter's bunny was getting very skinny and her hair seemed thin. Yet she seems very happy, hungry and active.  The vet visit referred us to a hospital and the hospital did a sonogram (6 cm kidneys)or 6 times the normal size of a regular bunny, bunny weight 2 kg, very underweight. And biopsy of kidneys, diagnosed lymphoma. We hear this is rare. $450.00 for both visits just to confirm the problem and really nothing we can do.  So we brought her home, she seems happy, but we realize time is limited.
She is so sweet.  Could diet have made this mess?  Our bunnies have different diets somewhat.  Since my daughter works all day she gives her bunny extra treats, like ricekrispies, alfalfa, yogurt drops, bird seed along with her regular pellets and carrots and apples.  My bunny eats pellets, oats, kudzu, banana, apple, dandelions and other grasses and leaves.  Her bunny is in a cedar townhouse mine is in a metal cage (one floor).  I have always fed my bunny quality hay and talked my daughter into using the hay for bedding and bathroom like I do mine only 6mths ago.

Answer
Dear Deborah,

I am so sorry about this very sad diagnosis and poor prognosis.  Yes, it's true that this is pretty rare.  But please don't blame yourself.  This is more likely something she has been carrying inside her genes, and there is nothing you could to do predict or prevent this.

Love her, spoil her, and--I hate to even suggest this--but you *might* consider trying to introduce the two girls to a neutered boy from your local rabbit rescuer.  If the three can bond, then when your little one finally does cross the Rainbow Bridge, then her sister will not grieve so deeply if she has a friend to comfort her.  

If you do decide this might be something to think about, you can find a rabbit rescuer here:

www.rabbit.org/chapters

I hope your bunny will have lots of quality time left, and that her passing will be gentle and surrounded by love.  She is lucky to have such a caring family.

Take care,
Dana