Until she wound up marrying the plunger.
These are the ultimate in tasteless jokes, which I learned when I was a kid as well.
We also had a whole slew of Little Timmy jokes.
*A: Mrs. Johnson, can Little Timmy come out and play baseball?
B: You know that Timmy has no arms and legs.
A: Yes maam, but we need a 3rd base.
A: Mrs. Johnson, can Little Timmy come out and play?
B: You know that Timmy has no arms and legs.
A: Yes maam, we just wanted to put him on the hot sidewalk and watch him flop around.
*
My mom was a paraplegic from polio. Guess where I first heard quadriplegic jokes from?
What do you call a quadriplegic on the porch?
Matt
What do you call a quadriplegic nailed to the wall?
Art
What do you call a quadriplegic in the pool?
Bob
What do you call a quadriplegic in a hole?
Phil
What did the parents name the boy who had no lower legs?
Neel
What did the parents name the girl with no lower leg on one side?
Eileen
And of course the Japanese girl with one leg was named Irene.
Why was Helen Keller a virgin?
Her parents could get her a seeing eye dog and a hearing ear dog, but not a fucking cunt dog.
How come HK didn’t skydive?
It terrified her dog.
What do you call a tennis match between Helen Keller and Stevie Wonder?
Endless love.
I’ve got internet searches that prove this wrong.
Brought back memories of Dean Potter abusing his poor little dog!
I’m with your grand-daughter.
Go easy on her, she had to type that with half the hands Helen Keller had.
The version I knew: They rearranged the furniture.
Maybe she needs some dead baby jokes instead.
What did Helen Keller say when she fell off the mountain top?
Nothing, she was wearing mittens.
Best one so far 
I don’t have another HK joke, but this thread reminded me of the boss at my first real job. She had a wicked and irreverent sense of humor, and referred to the Marketing department as “the Helen Keller Marching Band.”
Claimed in this people weekly articlefrom 1989. Don’t know if this would be considered a reliable cite.