The Wanted singer revealed last year that he had been diagnosed with an inoperable brain tumour.
He has now shared that Maggie May singer Sir Rod – who previously battled prostate cancer – was among those to offer him support.
The Mirror quoted Parker as saying: “Rod messaged me saying, ‘Listen, I’ve been through this situation. If you ever need to rant, I’m here for you whenever’.
“What a lovely thing to do. It was so nice of him to do that.”
Parker told his fans in October 2020 that he had been diagnosed with stage-four glioblastoma, while his wife Kelsey was expecting their second baby.
Sharing a picture on Instagram showing him in a studio, the chart star wrote: “Ok… here goes.
“The last couple of days have been filled with dread and worry but I’m pleased to announce that the results of yesterday’s scan (lovely birthday present), are stable with a slight reduction in the tumour if anything."
“I can’t tell you how grateful I am to receive this news," he told his fans.
In 2019, Sir Rod revealed he had beaten prostate cancer after battling the illness in secret for around two years.
The singer, 76, said that he was diagnosed with the condition during a routine check up in 2017 and was given the all-clear in July 2019.
Watch: Rod Stewart buys wife a boat for her birthday