"Dirty old folks" joke

Harold is 95 and lives in a senior citizen home. Every night after dinner,
Harold goes to a secluded garden behind the center to sit and ponder his
accomplishments and long life.
One evening, Mildred, age 87, wanders into the garden. They begin to chat,
and before
they know it, several hours have passed.
After a short lull in their conversation Harold turns to Mildred and asks,
"Do you know
what I miss most of all?"
She asks, "What?"
"SEX!" he replies. Mildred exclaims, "Why you old fart, you couldn't get
it up if I held a
gun to your head!"
"I know," Harold says, "but it would be nice if a woman could just hold it
for a while."
"Well, I can oblige," says Mildred, who unzips his trousers, removes his
manhood and
proceeds to hold it. Afterward, they agree to meet secretly each night in
the garden
where they would sit and talk and Mildred would hold Harold's manhood.
Then, one night, Harold didn't show up at their usual meeting place.
Alarmed, Mildred
decided to find Harold and make sure he was O.K.
She walked around the senior citizen home where she found him sitting by the
pool with
another female resident, Ethel, who was holding Harold's manhood.
Furious, Mildred yelled, "You two-timing creep! What does Ethel have that I
don't have?"
Old Harold smiled happily and replied, "Parkinson's."