Ay, ganyan din yung situation ng kaibigan ko kaya alam ko how stressful yan! Honestly, constipation from formula is super common sa toddlers, and switching brands alone might not solve it, kailangan talaga ng doctor check-up para malaman kung may underlying issue or if kailangan ng different approach beyond just lactulose. A few of us tried adding more water, fruits (especially pineapple and papaya), at less milk para a bit, pero since lactulose hasn't worked for your LO, mas maganda na makonsulta ang pedia para sa proper evaluation at possible prescription na mas effective. Some mums swear by HiPP or Friso dahil gentler sa tummy, pero talaga, check with the doctor muna bago mag-switch ulit ng milk kasi baka may ibang factor na hindi nakikita. Fingers crossed for your baby, mama!