Should I worry about my child’s speech? Everyone understands him but he sounds "funny".

Most of the referrals that I get are for kids with “funny” speech.  Parents say, “everyone understands them.”  But…they have a “wobbly r”, “slushy speech”,  ”sound like they are from Boston”. If your child can’t say some sounds, namely the r, s, or th correctly, but everyone understands them, don’t be too concerned. If it