Though Avril hasn't commented on her problems or confirmed the legitimacy of the messages, she publicly responded to the Twitter account after they sent well wishes, writing simply: "thank you".
The Girlfriend hitmaker's rumoured health woes come a few months after speculation her marriage to Kroeger - who she married in July 2013 - was in trouble.
However, the This Is How You Remind Me rocker later laughed off the reports, which were fuelled when he missed Lavigne's 30th birthday party.
He admitted even his family had worried about the status of their relationship.
The 39-year-old rocker said: "You know my dad calls me up and he's just like, 'I haven't slept in two days, what's going on?' I'm like, 'Dad you're not buying all this crap are you?'
"You know, I get to hear all the rumour mill stuff. So it's, it's ... I find it very amusing."
MailOnline has contacted a spokesperson for Avril for further comment.
- Daily Mail
