Question: how is PAL Express and Philippine Airlines connected?

Context articles: Philippine Airlines fleet
Iloilo-Negros Air Express
Mariano Yenko
Philippine Airlines Flight 158
Ninoy Aquino International Airport
Air transportation in the Philippines
Philippine Airlines
Philippine Airlines Flight 215
PAL Express
Provincial Airlines

The Philippine Airlines fleet composed of wide-body and narrow-body aircraft from four families (excluding PAL Express fleet): Airbus A320, Airbus A330, Airbus A340, its flagship Boeing 777, and it has the Airbus A350 on order.
 As of 2 January 2017, there were 55 aircraft registered in the PAL fleet.
Iloilo-Negros Air Express Company, Inc., which operated as Iloilo-Negros Air Express or INAEC and later as FEATI, was an airline based in the Philippines.
 The airline was folded into the operation of Philippine Airlines (PAL) which was re-nationalized by the Philippine government and became the national flag carrier.
 The company built the Bacolod International Airport in Bacolod City, which was bought by PAL after the acquisition of the airline.
Colonel Mariano Yenko was the second commissioner of the Philippine Basketball Association.
 He served as the Assistant Executive Secretary under Philippine President Ramon Magsaysay and as Philippine Airlines' Vice-President Corporate Secretary.
 The Ateneo de Manila University's Audio-Visual Room at the Moro Lorenzo Sports Complex was named after him.
 His son Ignatius Yenko served as PBA's Chairman and as PLDT's First Vice President.
Philippine Airlines Flight PR158 was a Philippine Airlines flight from Mactan-Cebu International Airport to Manila International Airport in Manila which crashed on 12 September 1969.
 The aircraft, a BAC One-Eleven, struck a mango tree on the hill in suburban Kula-ike, Antipolo City, 22 km east of its destination while on a VOR approach to runway 24.
The Ninoy Aquino International Airport (Filipino: "Paliparang Pandaigdig ng Ninoy Aquino" ) or NAIA , formerly known and still commonly referred to as Manila International Airport (IATA: MNL, ICAO: RPLL) , is the airport serving Manila and its surrounding metropolitan area.
 Located along the border between the cities of Pasay and Parañaque, about 7 km south of Manila proper and southwest of Makati, NAIA is the main international gateway for travelers to the Philippines and serves as a hub for AirAsia Philippines, Cebgo, Cebu Pacific, PAL Express, and Philippine Airlines.
 It is managed by the Manila International Airport Authority (MIAA), a branch of the Department of Transportation (DOTr).
Air transportation in the Philippines goes back to the early days of aviation prior to World War II, during the American colonial period of the Philippines.
 Currently, the Philippines has several registered airline companies, but they are mostly chartered.
 There are two main domestic airline groups doing business as Philippine Airlines and Cebu Pacific, with AirAsia Philippines competing on some international routes.
 The domestic market is dominated by the Cebu Pacific group which has a 61% market share, followed by the Philippine Airlines group which has 29%, followed by AirAsia, having a 9% share.
Philippine Airlines (PAL), a trade name of PAL Holdings, Inc. (PSE: PAL), also known historically (until 1970) as Philippine Air Lines, is the flag carrier of the Philippines.
 Headquartered at the PNB Financial Center in Pasay City, the airline was founded in 1941 and is the first and oldest commercial airline in Asia operating under its original name.
 Out of its hubs at Ninoy Aquino International Airport of Manila, Clark International Airport of Angeles and Mactan-Cebu International Airport of Cebu, Philippine Airlines serves 31 destinations in the Philippines and 41 overseas destinations in Southeast Asia, East Asia, Middle East, Oceania, North America and Europe.
Philippine Airlines Flight 215 was the route designator for a Philippine Airlines flight from Cauayan Airport to Manila International Airport which exploded en route to Manila.
PAL Express, formerly Air Philippines and Airphil Express, is an airline operating under the business name of Air Philippines Corporation.
 It operates domestic and international scheduled services from Manila, Cebu, Davao and Zamboanga.
 The airline has been re-branded a number of times, first as Air Philippines, then Airphil Express, and is now known as PAL Express.
 After a series of financial losses, Air Philippines ceased operations until it was acquired by investors from Philippine Airlines.
 After the acquisition, the airline was re-launched as PAL Express, operating some routes and slot assignments of its sister company Philippine Airlines until management decided to re-brand the carrier as a budget airline known as Airphil Express.
 However, in March 2013, the company's CEO announced that the name would be reverted to PAL Express.
 As a codeshare partner of Philippine Airlines, PAL Express operates as a full service carrier within a low-cost model.
PAL Airlines (formerly Provincial Airlines) is a regional airline with headquarters at St. John's International Airport in St John's, Newfoundland and Labrador, Canada.
 PAL operates scheduled passenger, cargo, air ambulance and charter services.
 PAL is the commercial airline arm of the PAL Group of Companies.
 In addition to its head office, it also has offices in Halifax, Nova Scotia (Halifax Stanfield International Airport) and Happy Valley-Goose Bay (CFB Goose Bay).
 PAL is the second largest regional airline operator in Eastern Canada next to Air Canada Express.