pass a variable from one page to another

hi
i want to pass a variable from one page to another. But i don’t find the right syntax!
my snippet in the first page

$toto = 25;
header('Location:https://www.inscriptionsoccervg.ojjo.ca/inscription-un-poussin/?mavar='$toto); 

but have he error message : syntax error, unexpected ‘$toto’ (T_VARIABLE)
i try
header('Location:https://www.inscriptionsoccervg.ojjo.ca/inscription-un-poussin/?mavar='.$toto);
but it doesn’t work.

and the snippet code in the second page

$mavar = $_GET['toto'] ;
echo "Loop start!", $mavar;

could you help me please ?
thank