Instruct: Classify a given Amazon review into positive or negative sentiment.
Query: warning! babies have to be able to sit up on their own

i received this as a gift for my 4 1/2 month old who can hold up his head pretty well and is attempting to pull himself up, but not yet sitting unassisted. we put him in this exersaucer and he immediately fell forward and hit his face on the edge of the padded seat. i read in consumer reports that babies should not be left in this exersaucer for more than 5-10 minutes at a time because it can cause their back to compress and grow crooked. also, babies should really be more like 8 months old before put being put in it. the box says 4 months and up but the directions (in an inconspicuous place) say baby must be able to sit up on his own.