On the Info Panel of a selected person You can (should) see 4 Buttons. Info, Events, Family, Photos.
Tap the 2nd one (Events) and You will see some events. In the upper right corner of this panel there is an Edit button. After tapping this button You will see Add events under the persons name. Tapping this one You will see 7 general Events and All events. Scroll down and You will find the baptism event.