KINGWOOD, Texas (CNN) – A Texas mother is outraged after she put a sweet note in her 5-year-old son’s lunchbox, only to get a nasty note from the daycare in return.

The 5-year-old’s mother, only identified as Francesca, says her son has been going to Rocking Horse Day Care in Kingwood, Texas, for three years, and she never had any problems.

But on Tuesday, she made dietary changes for his lunch and wrote a note to be supportive, asking workers to “Please tell my son that his mommy loves him so much and that I’m thinking about him.”

“I do everything in my power to build my son up and make him feel good about himself because he is amazing,” Francesca said.

The note came back in the lunchbox that night with a message written at the bottom: “No! Put him on a diet and go away.”

“It took a minute to register what I even saw, and I just kept re-reading it, and I just stood there for a minute,” Francesca said.

The mother alerted the daycare about the incident. The director apologized, and after an investigation, the employee who admitted to writing the message was fired.

“The thing that upset me the most is this is bullying,” Francesca said. “To know a grown-up, who knows how hard life is and how mean people can be, can say something like that, especially about a child, is – they’re sick. There’s something wrong.”

The fired employee said they never intended for the mother to see what had been written.

Francesca is now trying to find a new daycare for her son. She has been taking him to work with her until she can do so.

“I put a lot of trust into this school to take care of him, and it just really hurt me,” she said.