Houllier will spend the Easter weekend under observation at the Queen Elizabeth Hospital in Birmingham after falling ill on Wednesday night. Assistant boss Gary McAllister will take charge on Saturday and it remains to be seen whether Houllier will return to the dugout before the end of the season.
England winger Downing told the club's official website: "Obviously, everyone at the club is concerned for the manager. It's never nice, an experience like this, especially for his family."
He added: "But the news is that he's going to be all right and that's pleasing and reassuring. A good win against Stoke on Saturday will help him no doubt.
"In fact, the last couple of weeks have been good and I'm sure the gaffer will want us to continue in this vein.
"That's what Gary McAllister told us, that the gaffer wants us to carry on playing like we're playing and to win as many points as we can between now and the end of the season.
"Hopefully, a good result on Saturday will be the perfect boost for him."
Striker Darren Bent echoed Downing's sentiments, saying: "All of the players wish the gaffer a speedy recovery.
"We want him to be back as soon as possible. But his health comes first and we need him to get better and hopefully he'll be back soon."
Source: PA
Source: PA