is it true that if a bitch comes in season ,it brings all the other bitches in has well

Not exactly true, but if a bitch who is due a season is housed with other bitches that are in season - It can bring her into season.  :)

hi at what age do bitches stop coming in to season
my dog is eight  this year and she is in season at the moment

it has been said that bitches kennelled together will have seasons at the same time, this isnt always true, our bitches have seasons at varied intervals during the year, and it never seems to be influenced by other bitches in season but ive heard other people say their bitches are different. it works out best for us that they dont alll have seasons at the same time as we prefer to have some spaces between the litters rather than have several all at the same time :-)

They don't. They usually go on having seasons all their lives.

at what age do sibs have there first season,as mine is 6 months and i'd like to know what are the tale tell signs,as i don't what any little mistakes! thanking you for your advice.