Mr Kolomiichuk travelled from Kyiv to Lviv and was able to spend an evening and day with his family.
Mr Baker said it was emotional “for me to meet the man whose family I’ve been privileged to look after for the last seven months”.
He said Sviatik, who has recently turned seven, had “no ability to speak English” when he arrived in the UK, but was now fluent.
The MP said the boy’s father “noticed these huge changes in his son”.
“It was a heart-warming few hours to see him with his dad,” he said.
He said it was “painful and emotional” for them to “say goodbye” as they did not know when they would see each other again.
“But I was able to say to him ‘your family are in safe hands’,” he added.
The MP, Mrs Kolomiichuk and her son have now returned to the UK.