“Sisina’s themes are offering, prayer, love, devotion, home and relationships. Her symbols are Spring and May-blossoming flowers. This Filipino Goddess oversees the realms of orderliness, beauty and love. Traditionally, She protects marriages against discord, but She may also be called upon to settle inner turmoil within you soul and restore self-love.
Today concludes Flores de Mayo in which people in the Philippines say good-bye to May with bouquets, flower offerings and an array of sweet foods to honor the month’s sweetness and beauty. Sometimes they ask Sisina to joint the festivities by setting a place for Her at the table.
This particular custom appears in several other cultures and it is a simple lovely way of honoring the Goddess. Just leave a plate with a a fresh flower on your dinner table. This draws Sisina’s presence, love and peaceful nature to your home and family relationships. If you wish also leave an offering of sweet bread or fruity wine in a special spot to thank Her.
As you go about your normal routine today, take time to enjoy any flowers you see and be very considerate of the special people in your life. Sisina will see the effort and continue blessing those realtinships with harmony.”
(Patricia Telesco, “365 Goddess: a daily guide to the magic and inspiration of the goddess”.)
I could find no specific mention of a Goddess called “Sisina” for today’s entry. While browsing through a list of Gods, Goddesses and Deities of the Philippines, I did find 2 Goddesses of love. The first Goddess I found was Dian Masalanta, “the Goddess of love, pregnancy, child birth, and peace among the ancient Tagalogs. Ever since the arrival of the Spaniards, She has been known by the name, Maria Makiling, after Her mountain, Mount Makiling.” 
The second Goddess I found was Sehana, the Goddess of love who had the power to bestow love on any mortal or immortal being.  I could find no other information on Sehana other the meaning of Sehana as a Filipino name for girls.
I did find mention of a Goddess called Bighari, who was the Goddess of flowers and daughter of Bathala (the supreme god of the ancient Tagalogs) who plays a role in the Filipino legend of the first rainbow. Legend says that “one day Bathala planned a journey to Earth to visit his faithful people. He called his children to bid them farewell. All of them came but Bighari, the Goddess of Flowers. Bathala, who valued promptness, became angry because this was not the first time that Bighari missed their gathering. Thus, he banished Her from their heavenly kingdom. Bighari, at that time, was at Her garden on Earth. She wept bitterly when She was told of Her banishment. But She sought to cope with Her sorrow by causing Her garden to bloom profusely.
The legend of the rainbow says that the people that used to live around Her garden grew to love Her more and more for bringing beauty to their lives. They resolved, after a time, to build Her a bower so that they could see Her garden even from a long distance.
And so they built it, and decked it all over with colorful blooms. Thereafter, whenever Bighari would travel, people would see Her colorful bower against the sky.” 
Mysterio delas Filipinas, “The Eternal Beings“.
Read-legends-and-myths.com, “The Rainbow Legend from the Philippines“.
WikiPilipinas, “Dian Masalanta“.
Nosfecatu Publishing, “Taste Test: Dian Masalanta“.
Wikipedia, “Deities of Philippine Mythology“.