Area 8: Empty Area
2nd Hot Spring
» Empty Area
» anytime
» Use the 1st Hot Spring 100 times
Once you get the 1st Hot Spring by triggering Flora's Blue Heart event or by waiting until your child is born, you can use it to recharge your Fatigue points. If you want to recharge your Strength points you're going to need to activate the event to unlock the second spring.
To unlock the strength-recharge spa you will need to use the 1st one 100 times. You do not need to stay inside of the hot spring for any specific length of time, so just walk in and out of the door until you see Thomas appear. He will notice you seem to really like hot springs and have a second one built for you.
The 2nd hot spring will appear right next to the Sprite Company tree near the Goddess' pond.