Re: 14 mos, no longer wants mommy milk during the day
First, I just wanted to say that it's fairly common for kiddos to stop wanting breast milk when mom's not around once they've hit the one year mark. My daughter started refusing bottles at 13 mos, which is ultimately why I quit pumping. So that's not so much a concern, especially given your nursing patterns.
I'm not sure how the tablet compares with gatorade or other 'electrolyte' beverages, but I know those are big no-nos for kids. The amount of sodium makes me cringe. And all those chemical sweeteners- I'd rather pump straight sugar into my kid. She's still so tiny, there is really no telling what that amount of electrolytes (which I assume is in a dosage meant for a full grown ADULT and not just an adult, but one who is sweating so hard they are LOSING ELECTROLYTES, what is that doing to her body? Her kidneys are surely working overtime to handle all that. Seriously, I really think you need to be more concerned about it.
Okay, well all that aside. I agree with others that the issue here is your husband. If the issue is that he can't get her to drink water and he's not willing to try to force the issue (he does realize that he's the grown up and she's the baby...right?) then maybe you could find a compromise. Would he comply if you told him fine, you don't have to force water on her, but no more tablets. If she's thirsty give her something she will drink like the smoothie or...jeez, I'd even be more comfortable with diluted apple juice or something.
“We are not put on earth for ourselves, but are placed here for each other. If you are there always for others, then in time of need, someone will be there for you.”