The unusual gesture was captured in a viral video and attracted cheers from students as Chinyere presented the goat to her son before embracing him.
Speaking in an interview with BBC News Pidgin on Monday, Chinyere said the gift was her way of rewarding Promise for making her proud, obeying her instructions and staying away from cultism.
She said she had promised to surprise her son if he successfully completed his studies without disappointing her.
“I don’t have money for a 4matic jeep, and I love that guy, my son. I said, let me buy this goat as a gift,” she said.
Chinyere said she had warned Promise against joining cult groups when he started his studies and urged him to complete his education.
“When he was going to school, I told him not to affiliate himself with cultism and to make me proud by not dropping out. I told him that if he made me proud, I was going to surprise him. He didn’t disappoint me,” she said.
According to her, Promise has remained respectful to his family and others, while also pursuing his passion for football.
“He has been respectful to the family and everyone. He’s a footballer, and I want to prove my love for him. That is why I bought the goat for him,” she added.
Chinyere disclosed that she bought the goat for N120,000, saying she would have spent more to fulfil her promise to her son.
“I bought the goat for N120,000. I said even if it is N200,000, I will try my best to see that I come with that goat,” she said.
She also said she was delighted by the reaction of students as she approached her son with the animal.
“As I was walking, they (students) were screaming. I was happy, and I knew my son too was,” she added.
Promise, meanwhile, said he initially thought his coursemates were inviting him to an engagement ceremony after hearing students shouting, “say yes”.
He said he was surprised when he discovered that his mother had arrived at the school with a goat for him.
“It was one of my coursemates that called me because I thought it was an engagement serenade because people in the vicinity were screaming, ‘say yes,’” he said.
Promise said he was initially unsure whether the woman with the goat was actually his mother but became emotional after realising what she had done.
“I came, happy and deeply emotional. I wasn’t ashamed. I was extremely happy. I am not even ashamed in school; why then would I be ashamed of my mum or her action?” he said.
The video of Chinyere presenting the goat to her son has since attracted reactions online, with many Nigerians applauding her for celebrating her son’s academic milestone in an unusual way.