My experience from last year...
CP Newcastle - Stephenson Quarter (UK) : children allowed in to club lounge at all times of day
CP Birmingham (UK) : children not allowed in to club lounge at any time of the day - front desk said because there is alcohol in there - notice outside lounge said to "create a working and meetings environment"
Further discussion :
www.flyertalk.com/forum/intercontinental-hotels-ihg-rewards-club-intercontinental-ambassador/1699783-lounge-access-breakfast-crowne-plaza-properties.html