This could easily be dairy allergy/intolerance. Suggest she try dropping the
baby bottle, and see what happens. Increase other foods if necessary.
Why is the mom pushing weaning, anyway? 3 1/2 year olds are fun to nurse,
and usually quite negotiable.
Linda J. Smith, BSE, FACCE, IBCLC
Bright Future Lactation Resource Centre
Dayton, OH USA
http://www.bflrc.com