But rather than wrap up a new computer or mountain bike, the 34-year-old from Nashville, Tennessee, hired a stripper to perform explicit dances for her offspring.
Yesterday Mrs Pharris was left ruing her decision after she and husband, Landon Sr, were sentenced to two years' probation for delinquency of a minor and were obliged to take parenting classes.
Her brush with the law came about after "Sassy" the stripper danced scantily clad for 30 partygoers, most whom were under 18.
But when she had finished, they stumped up the sum of $150 (£90) for her to take everything off.
After being charged, Mrs Pharris said: "It's a bunch of bull. I tried to do something special for my son. It didn't harm him. Even grandpa was there. Age is just a number. My son is very mature."
But local police thought differently. "We don't think the Nashville community is ready to allow adult entertainment in the form of a nude dancer around teenagers at a birthday party," said police spokesman Don Aaron.
He noted that minors who were not related to the family had attended the party.
"Minors are not permitted in adult establishments in Nashville or anywhere in this state," Mr Aaron said.
The stripper, Cassandra Park, and the man she was with were also granted probation.
Police found out about the party after Mrs Pharris took pictures of the party to be developed.
According to the police, Mrs Pharris handed the camera to her then 14-year-old son, Brandon, for some photographs.
"Who are they to tell me what I can and can't show to my own children?" asked Ms Pharris, adding: "Let he who is without sin cast the first stone."